Theoretically, every car-insurance policy holder could switch carriers a couple of times a year, because most policies have six-month terms.

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In fact just the opposite can be true among poorer and less-educated drivers, according to a recent investigation of car-insurance policy pricing conducted by the Consumer Federation of America in Washington, D.

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Lessons learned: know some Italian before visiting Italy, and take out the full insurance policy on your rental car.

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Enterprise does a special insurance check to make sure a customer's policy transfers over, though in some cases credit cards also provide rental-car insurance.

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